Well everyone is entitled to his/her opinion so it’s certainly not bad to upgrade your collectors and mines. It has a big advantage if you can be online often to empty them, and you will never run out of gold or elixir for a long time to raid again (I usually make sure it doesn’t happen but you never know).
But that’s only important if you’re casually playing this game. Me for example raids more than I can even use - which means it gets stolen because my walls were maxed, thank god I finally go to TH9 to have a new resource sink). Some extra loot from collectors and mines doesn’t help me at all.
Another thing to consider is that they are very cheap but take a long time to upgrade. I like to use them as fillers in case I have no time to raid but have a free builder. That’s why my collectors aren’t totally neglected but all around level 9 and now all going to level 10. I expect that once the upgrades will become more costly I will put them more often between upgrades, though.
Played once CoC in the past... came back on December 6, 2018, with a fresh account. Same name: Raging Rabbit. TH8. Clan: ClashPros.