So I work in a fab shop of sorts with a small handful of other employees. I've been there for several years and have unofficially become the shop foreman or floor manager or whatever just by nature of being the only person that knows how the place runs. I'm not a good manager – I absolutely hate telling people that they're wrong – but I know the process and everyone likes me, so it works out. My boss, who is also the owner, doesn't really know all the details of the work we do, but he used to do my job some 10 years ago and tends to think things are still the same as they were then.
He mostly lets me do my thing and lets me assign tasks and run the shop, but in a way, he's kind of over-involved in some details like inventory management. I do my best to track it with my own spreadsheets that I've made over the years, and I do some legwork for finding suppliers when there are issues, but when it comes time to order materials, the way it works is I sit down next to bossman at his computer and we go through every item on my lists and he manually checks several different websites to find the best prices. Sometimes just looking for one item can take 20 minutes because Amazon will have multiple similar items and we have to go through them all as I tell him why they won't work until we eventually get back to the one I told him was what we needed.
Another thing about him is that he is a massive tightwad who aims to only buy exactly what is needed for each individual job as we do it. Anyone who has done this sort of work knows that this is a recipe for running short which is exactly what happens quite frequently. I've gotten a pretty good idea of the kind of quantities needed for each job, and he mostly trusts me to track that, but sometimes he just won't get enough of some things.
Tools are another big issue where he refuses to acknowledge that they wear out and break sometimes. He'll eventually get something, but generally cheap stuff and we have to wait forever since he'll find it from china for $2 less than it is locally. Also, related to not knowing how tech has changed, sometimes he can be pretty belligerent about not buying the right item when he used to do it differently. I'm certified in what I do which carries with it some responsibility to do things right, but sometimes he doesn't see the point when the right way costs more money. It can seriously be like pulling teeth to get him buy what we need when we need it.
So, onto the confession part. I've started doing a bunch of side work for myself in the same industry where I use a lot of the same parts and materials. Since he really has no idea on quantities, I've gradually been able to get him to overstock on some of these items that are especially hard for him to mentally track. I then use these materials to do my side work where I keep accurate invoices tracking the cash related to these materials. Then, when we run into a situation where someone needs something right now to do their job, I'll run by lowe's at lunch and get what we need using that cash.
I don't feel bad about it whatsoever since I'm not actually stealing value from the company. I've tried for a few years now to get him to change his ways, but he is super stubborn and, like I said, I have a really hard time telling people they're wrong. So whenever I do say something, I just let myself get walked over. Should I feel bad? Is this ultimately unethical? Curious about people's thoughts here.