Theme parks are expensive. Children over 12 have to pay full price to get in, the best rides cost extra and you could feed a family of four for a week for the price of buying a few plates of unappetising chips there. It’s hardly staggering news. Am I the only mother whose first thought when she read the Which? report went something like “don’t teach your grandmother how to suck eggs”?

Somebody should tell the people at Which? that parents already know that anything that is commercial and “fun” will cost an arm and a leg. We know we will pay inflated prices to go away during the school holidays, even though we are not able to travel at any other time.

And that on certain airlines we will have to pay extra just to guarantee we can sit together as a family. As if anybody – even hard bitten airline executives - really wants distressed two-year-olds getting in the way of the drinks' trolley as they try to find mummy. Or that same mummy getting in the way of everyone else as she hovers in the aisle because she doesn't feel she can leave a small child unattended.

So it comes as no surprise to “learn” that admission to a theme park for a family of two adults and two children can cost in the region of £100. If it were any less we would probably think there was something wrong. Because, quite simply, when it comes to leisure and travel, families have got used to being fleeced.

And it's no good offering money-saving advice such as take your own picnic. I don't believe there's a child in the land who would choose sandwiches and fruit over the usual theme park fare of burgers and fizzy drinks. And are there really any parents out there mean enough to deny them sweets and ice creams on their special outing? After all, it's all part of the great day out.

Overexcited children cramming themselves with junk food and vomiting on the rides, or on the way home. I don’t think we’ve ever been on a day out that hasn’t involved an extremely dangerous “sick” stop on the hard shoulder of the M25.

Inevitably, the theme parks say they provide value for money. And, just as inevitably, parents beg to differ.

But, for all that, just as I wouldn't stop taking a summer break because I think it is unfair that families pay more during the school holidays, I wouldn't write off theme parks altogether just because I don't like paying over the odds for what is, essentially, a manufactured experience.

And though we’ve yet to try Legoland, which friends tell me is fantastic, I have very good memories of taking my then three-year-old daughter to Dizzily Land (Disneyland Resort Paris). And yes, I have to confess that we were totally sucked in. That seeing her face light up when Mickey Mouse gave her a hug really did bring a tear to my eye. That we enjoyed Dumbo the Flying Elephant and It’s a Small World and that we bought giant lollipops and a Mickey Mouse mug in the shop.

But I wouldn’t go every day. Or even once a year. Theme parks are strictly for special occasions. Maybe a birthday treat, or day out during the school holidays. The rest of the time – at the risk of sounding holier than thou – we are content with making our own “fun” for very little money at all.

My children love getting together with a gang of friends in our local park. The cost? Eighty pence each for a Mr Whippy. They claim to hate, but actually love, rambling around the English countryside with us. Cost? Nominal amount for petrol, plus 80p each for a Mr Whippy on the way home. They also know that when the weather is rubbish or we are busy or broke or all three, we will have to stay home and watch The Sound of Music.

Parents know that, whatever story the theme parks spin about value for money, we are being ripped off. And that we could probably amuse ourselves at home for far less. But every once in a while, most of us are prepared to go down that road. Not because we are stupid or too weak to resist pester power but because visiting a theme park, a bit like going on holiday, provides us with a chance to escape the ordinary, forget our usual preoccupations, and spend some time together. Sometimes, just, very, very occasionally, we are prepared to pay through the nose for that.

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