to expect the parents-in-law-to-be to help out with our wedding?

[nearlyuptheduff]

So far my parents have footed the WHOLE bill, his parents have not offered to help or contribute.

AIBU?

I wish we'd never got married how different things would have been if i'd had an new kitchen instead.

Jesus OP sounds like you are getting annoyed at the wrong thing. Why do you care what they are contributing to the wedding when your FIL has been bullying and taking advantage of your Dad like this?
If this had happened to my Dad I would be having a serious showdown with the ILs and putting them straight in no uncertain terms that that sort of behaviour towards my family is completely unacceptable. No way would I have my wedding hijacked and used as a stick to beat my Dad with.
Cancel the hotels and taxis and tell them to sort them out themselves. Tell them quite frankly they are lucky to be invited at all.
What money your ILs are contributing is the least of your worries.