Guess DH and I are just naturally thrifty people and this carries over with our WDW trips. We sometimes use our Delta miles for free airfare (from HI) or combine it with a trip to the east coast to see family. If not, DH watches the ticket prices for months and buys when they hit bottom. (I swear it's become a hobby and he gets great pleasure from this!)
For hotels, we do not stay at deluxe resorts, but take advantage of Shades of Green since DH is military. We go in the off season and sometimes get the breakfast/room package. (We do visit the deluxe resorts and enjoy their atmosphere and restaurants, such as AK's animal park, Sanaa or the GF Cafe) If not, we take instant oatmeal or other quick breakfast snacks and plan for an early lunch, which cuts out breakfast expenses. We don't rent a car, but use the park transportation system. For us, the hotel is a room and we want to spend as much time out of it as possible. If we were to pop for a deluxe resort, I would want to enjoy the resort, not just use it as a place to sleep. You can just sleep cheaply anywhere.
In the park,we carry small water bottles that we refill at water fountains- never noticed any different taste to the local water. We also bring a few granola bars, etc for a quick snack during the day. We do ADR restaurants only once a day, and not every day. If we aren't starving, we will often split a plate, such as the ribs and chicken at AK's Flame Tree. After many $$$ meals where the food was just so-so, an ADR has to be a theme or event we will enjoy, such as SciFi or Germany's buffet, and never just a chow stop or place to eat. We generally choose moderately priced dishes, too, not the most expensive items. And, we rarely buy snacks- maybe an ice cream sandwich we share when the park closes (and that's not every time). To be honest, we enjoy the food at many counter services (like MK Harbor House and Morocco's Tangerine Cafe) more than some of the sit down places.
As for souvenirs, etc, we don't buy much for ourselves. I get a new Villains cup if I really like it and every couple of years DH gets a new hat. We do not collect vinylmation, Christmas decorations, etc, but I did pick up a set of Mickey measuring cups and spoons and a Mickey Halloween jackolantern over the years.
Bottom line is to simply make sure what you spend your money on is something that you really want/need/enjoy and is not just frivolous. Nothing wrong with deluxe resorts, snacks, and souvenirs, but make sure it works for what you want out of your vacation and memories.
) That got us our 50,000 points so our airfare for our April 2016 trip is already taken care of
