Frankly, yes. Splurging on that Bugatti's isn't only going to cost you that much. There's depreciation, maintainence, everything. Sure, you might say, "But you've got 25 million quid!" but yea, they do all add up. I might spoil myself a little bit - that 70-200 f/2.8 IS II USM is looking really good, but I doubt I'll buy anything above a million quid within the next 20 years.
Personally, I'm content just living off the interest. Not working to survive, that's good enough for me. I've been living like that since I was born. I don't see why coming into a lot of money would change that. I rather much prefer the financial assurance to fall back on rather than to splurge 80% of it on stuff that's going to be worth considerably less in the next year.
EDIT: If anybody is wondering, THIS is partially the reason why I say I'm wa-aay older than eighteen. :)
EDITEDIT: I wouldn't be cycling past the mansion - I'd be on my mountain unicycle. :D