YANBU you should do it how you want. But weddings can be cheap, certainly cheaper than a holiday abroad, and it might be a lot easier than dealing with the grief from family when they realise what you've done.
We got married last year after 14 years together. We could have and would happily have done it on a shoestring, but when my Dad started talking about booking halls that that held 200 and were £6000 I decided inviting 30 people for a pub lunch at £18 a head was more than reasonable. We could easily have invited less.
We got married at the registry office, pub lunch after with family and friends.
For the evening we sent an open invite out to everyone we knew and told them what pub we were going to be in. The pub was a city centre one and we had our own room, DH mixed a load of CD's and we had our own disco (Pub provided the DJ decks for free). We put a £100 deposit down for the room but we got that back because our friends are alcoholics and drank the required amount of booze :0 (and we invited any random strangers who liked our music to join us.)
DH wore a suit he already had and some new converse he desperately needed!
3 outfits for bridesmaids (DD & DN's) cost £75, that included dresses, cardies, undies, shoes, the lot! They've all worn them loads afterwards too.
My dress was a luxury at £95 in the sale but I will wear it again. DrMarten sandals cost £20 off ebay :o
Probably the most expensive thing proportionally was the flowers, they cost £40 and I left them to my Mum to sort. I was talking about picking a load out of the garden :)
DH and I delayed for so long because I didn't want the hassle of organising it, family politics etc. I'd thought about eloping, but decided the upset it would cause wasn't worth it.
In the end we made the decision, booked the registry office and were married 5 weeks later.