I also keep a bag packed with toiletries including my own shampoo, conditioner, lotion, toothpaste etc. My hair is colored and highlighted and I use Bumble & Bumble products 75% of the time. Most hotel product is very drying, the H2O stuff turns my hair into unmanageable straw. I wash my hair 2-3x a week, unless I go in the pool or beach, so only need a small travel size container for vacation.
There is an Estée Lauder factory near me that opens on Saturdays to sell off overstock and those product giveaway bags from retail promotions. I go once or twice a year to stock up on discounted full size as well as travel size merchandise.