>I suspect it's not seen as a problem by providers because more lines generated means more tokens used and hence more billing put out on customers.

I have also grown skeptical of token usage in order to run up my bill! But since I feel like it takes me MORE effort to write LESS lines of code myself, I'd expect a quick and dirty AI-generated solution to be MORE lines of code and cost LESS to generate than a concise/elegant solution in LESS lines of code.