You're absolutely correct, and I know it's not best practice, although I rationalize it by pouring slowly and not doing it regularly. This is my 7th full season and after working my way through the learning curve in the first season with TFP and poolandspaforum, I shock an average of 2-3 times/year after opening. I'm also careful to disable the IntelliChlor before shocking.
There are worse offenses, in the beginning I would add Biogard silk sticks to the skimmer, then moved on to pucks (only while pump was running), but won't ever do that again. The only other thing I add to the skimmer is CYA, in a skimmer sock. No baking soda this year, after replacing liner and filling with city water my TA was 260! Been aerating and adding acid every other day and it's down to 140 now, aiming for 60 by this weekend. When I reached that level the last two years I was amazed at how little pH creep I saw, even with the salt cell.
All things I'm very grateful to have learned here. I used to chuckle to myself when standing in line at the pool store while watching pool owners leave with armfuls of stuff they would almost never need if they'd done some research and taken control of their water chemistry. Later I simply scratched my head. Now, I'm happy to say the only things I've bought at pool stores in the past 5 years or so are liquid chlorine, vinyl cleaner, o rings, eyeballs, skimmer socks and a skimmer pole - and even then only when I had an immediate need and couldn't wait to order it online at a better price.
Finding the white mold was frustrating but I'm confident it's gone, CC was zero this morning and again this evening. I'll let the FC drop over the next couple of days and then enable the cell. But I'll keep a couple of jugs of bleach in storage just in case...