I don't know how you can say "this is just done out of greed and disregard for coworkers" based on one bad experience. You might be surprised to find out that lots of engineers aren't well-utilized. I've never held multiple concurrent jobs, but I've been in positions where I'm only 25% utilized because of blockers and poorly thought-out plans. If the business doesn't regard me or my team members highly, why should we be obligated to sit and twiddle our thumbs? If we find something productive to do apart from our primary employment, are we "only doing so out of greed and disregard for each other"? I can subscribe to the "lying about it is reprehensible" bit, but I don't think "making yourself productive" or "maximizing your income" or "not slaving for your employer" is bad.
It's not like employers are committed to their employees; I don't see why employees should be faithful to their employers.
> Would I ever leave this company? Look, I'm all about loyalty. In fact, I feel like part of what I'm being paid for here is my loyalty. But if there were somewhere else that valued loyalty more highly, I'm going wherever they value loyalty the most.