A company invests money and engineers in building commercial tooling, which you then pay for because there is added value. You are not paying for the open source - which is freely available. How is that scummy?
The "comply with the license" part is the problem you're not seeing, using open source as SaaS is a loophole not a license feature.
An example being, I license something as open source which means if you don't pay for it (assuming there's an option for that), you are bound to follow the license I provided which means all further work has to be open source (the same license I used) and source has to be provided with the product. In an ideal world this would mean either:
1. We both get paid
2. We both contribute to open software which is available to anyone
But in our world it means, technically I'm not selling software but a service so I don't have to do shit. so the result (with scummy companies) is the following:
1. I don't get paid for software critical to your business
2. No one gets the benefit of the new product created despite my license
Hence, scum.
This is entirely untrue. If it were the case that 'I don't have to do shit', then why doesn't someone else do it too? Running a service takes a WHOLE LOT of work, and writing the software is, in many cases, the easy part.
We know this is true because whenever there is a conflict with a software license, the big cloud vendors just re-write it themselves.