What starbuck said. If at all possible, stay at the same hotel in each location and stay at the same chain. Once the hotel knows you, you will get automatic upgrades and/or free fridge/micros. Get to know the staff, particularly the management team. If you are allowed to make your own reservations, make them at the hotel. If you make them on line, tell them at checkout when your next trip is. That way they know exactly when you're coming back. When you make their top 25 guest list, you'll be golden, which sounds difficult, but really isn't. I used Holiday Inn and Marriott. I always made sure to get gold level for each. Hit the top levels and it really pays off. Toward the end of my career, I found Holiday Inn Express best suited/located for my needs, so I used them exclusively. When I retired, I got an IHG Rewards Club Platinum card that guarantees continued Platinum status, which pays off every time I stay in a hotel.
I have a small "picnic pack" that I take everywhere. It has backpacking utensils (strong plastic with knives that both cut food and get through airport security), a small fabric tablecloth, condiments (salt, pepper, mayo, mustard, soy sauce packets, hot sauce and a couple of wet 'n dry wipes.) The condiments have never been called, but you are allowed to carry on a lunch, so I'd use that loophole if needed. There is also a backpacker's can opener that's tiny and is just two hinged pieces of metal. It's so small that I've never had trouble getting it through security, YMMV. I carry a corkscrew only when checking luggage, which is seldom. I carry an inexpensive one, so that if I forget and put it in my carry on, it's no great loss. My "picnic pack" is a small zippered bag which flattens out when empty, so it's an easy shape to stuff anywhere.
A couple of other hacks have worked well for me. Since you are allowed to bring a meal on board, I have a lunchbox sized cooler that I fill with food plus a frozen blue ice. For good measure, I toss in a box of prescription meds. If challenged, I say it needs to be kept cold until opened (which is true). Once I've eaten what I brought along, I use the cooler for resupply. If I were buying something, I'd look for an expandable insulated bag that folds flat. Keep it small, so it can reasonably be considered appropriate for a carry-on lunch. I also carry water bottles that flatten when emptied. REI sells them, but I got mine at the Dollar Store, which is another good resource if there's one near any of your travel sites.
If a microwave is not available, a small immersion heater is great for boiling water (REI sells or online). The coffee machine always tastes like coffee and who knows how often it's washed. Ugh. Scrub out the pot and use the immersion heater to have hot water that doesn't taste gross. REI is a great source for backpacking eats that travel well and add more variety to your menu.
That per diem money can really add up. Good for you for using it to your advantage! A little creativity now will really pay off in the long run.