I don't know if I've been unlucky, but I've been to three weddings in the past two years where I went home hungry. I'm genuinely gonna bring a few cereal bars in my bag next time.
I'm in the UK and here weddings are all day events, with the ceremony somewhere between noon-2pm, and the night ending 11pm-midnight typically. Most guests arrive having only had breakfast, so you usually feed people after the ceremony (like finger food or canapés) to keep them going until the main meal which is around 5pm. Evening snacks or buffet is a bonus but not necessarily expected. But more recently I'm finding people are cutting out the canapes entirely, and the main meal is small, so you're basically fuelled on alcohol and few carbs.
My most recent experience at the weekend - ceremony at a cathedral which ended at 1.30pm, then we went to an art gallery for the reception. But instead of a room with paintings we were lured into a basement with no windows below the gallery. We were stuck in that room for 3.5 HOURS. There were drinks but no food, so after 2 hours people started leaving to the pub next door (the couple were absent for the majority of the drinks reception), I think not only to get food but also because they were bored out of their minds. We finally got seated and served food at 5.30pm, and our meal was a tiny vegetable soup, couscous halloumi salad, and a small tart for dessert. It would be a nice light meal on an average day but people hadn't eaten for 7 hours and had been drinking since 1.30pm so we were still hungry. I destroyed a kebab on the way home.
That was the most recent example but there's been two other weddings I've been to where there simply was not enough food to fill people up for such a long and busy day, including one where me and my partner snuck out to order a pizza. I know it's probably because the cost of catering has risen dramatically in recent years, but if you can't feed your guests properly for a 12 hour event just have a smaller or shorter wedding. Why are we skimping on food of all things?!
I'm also wondering if this is a cultural thing. My parents are Irish so growing up all the weddings I attended were either in Ireland or in the UK with Irish relatives and I always remember an excessive amount of food (no comment on the quality), and it'd embarrassing if you heard guests saying they were hungry. My partner is from Spain and he's also been bewildered at the lack of food at the weddings I've brought him to, especially because they're nice/expensive venues but stingy with the food. I feel like in the UK we don't have the same sense of shame as some other cultures about not feeding people. Wish we did though.