Over 16+ yrs of using web hosts, I've probably used over 60+ web hosts and currently actively using 19+ web hosts. Some of the nicest things some web hosts have done include
1. Free dedicated server hosting when i ran into some financial issues due to spike in growth of site which I couldn't cover financially at the previous web hosting and the server was down for hardware failure ~12-15+ yrs ago. Made up for it as back in the day dedicated servers easily ran into $500-1,500 month mark and referring probably over ~60+ dedicated hosting clients (don't recall exact number) their way from word of mouth as part of my consulting work is advising my clients on web hosts/server specs to choose and evaluating web hosts on behalf of my clients
2. One web host refunding my hosting payments 12+ months later after they did an audit and found out they overcharged me. They contacted me to say I over paid after a whole year !
3. Web hosts giving my referred clients heavy discounts on custom dedicated server configuration not available on their list prices/web sites
Not uncommon for me to refer up to 200+ clients to various web hosts per year
4. One web host was kind enough to suspend hosting payments for 6+ months, when I told them i was canceling due finances and not having the time to do the required testing I planned for the server. So they asked when I would have the time to use the server and suspended it until I had the time - so my data was intact just i wasn't using or logging into server while i was busy.
5. Web hosts lending me dedicated server configs for various benchmarking tests/reviews I do in my free time.
6. Lately, a few web hosts have been kind enough to provide free vps hosting as a way of supporting my Centmin Mod LEMP project (which they are fans of, use or just want to help), so test vps servers for various Centmin Mod related development and testing work (i.e. letsencrypt ssl integration work etc) as well as additions to my geodns cluster.
Been very fortunate overall for web hosting experiences over the years. Guess, this year has been the most troublesome with cloudshard.com closing down by Jan 31, 2017 and affecting 1 of my vps' directly and another 5+ vps indirectly (web host colocates with cloudshard) + wiredtree's acquisition by liquidweb !