We paid for literally everything 50:50 for about the first two years of our relationship. I insisted on paying my way as I wanted to be "equal" in all aspects of our relationship, right from day 1.
For big things, like holidays/hotel stays, we'd do bank transfers between us to equalise. For smaller things like meals, attraction entries, we'd even swap cash or we'd equalise as far as possible by say me paying for the entry fee and he'd pay for meals/snacks etc. If we went on a date to a pub, we'd take turns buying the drinks and made sure we had an equal number during the evening so we'd be "balanced".
The only really "different" thing was petrol - we both had our own cars, and rather than faff around thinking about petrol usage, we had an agreement that depending on whose car we used, the other would buy/bring the drinks and food for the trip. For a short afternoon drive, not much fuel used, so the other would just bring a couple of cans of coke and a couple of bags of crisps/chocolate bars. On longer trips/full days, the petrol usage was more, so the non driver would buy lunch/drinks/snacks throughout the day. That was really the only compromise on the strict 50:50 because we couldn't be bothered working out mileage and "per mile" costs!! But we did try to use each other's cars equally, neither of us being the main/dominant driver - we'd take it in turns to use our respective cars!
On holidays, we'd actually have a "joint purse", where we both put the same amount of money in it, and used it to pay for things we bought roughly equally, i.e. for meals, snacks, souvenirs, entry fees, bus/train fares, etc., so we weren't constantly swapping money. If one of us bought anything of different value, i.e. if I bought a T shirt and he bought a fridge magnet, we'd buy separately with our own money.
Over time, that "joint purse" turned into a joint bank account even before we were living together/married, where again, we each put an equal amount into it and used it for "joint" activities like days out, holidays, meals, etc., and then just topped it up when it was running low.
It was only really once we married and bought a house that we stopped doing the 50:50 thing and started treated everything as "joint" money.
I'd never have been comfortable either paying fully myself for a night/weekend away nor him paying fully for it. I never wanted any kind of power imbalance, right from my first date and always insisted on paying my way, not just with DH but also previous boyfriends that were far less serious.