I agree that 7zip is great (albeit based in Russia, so not something I'm sure I want to support at the moment), but consider for a moment that winrar licencing is primarily aimed at businesses (which is why they don't bother locking personal users out after the trial ends), and for that money you get a certain guarantee of functionality and stability over a long period of time.

There's absolutely no guarantees that 7zip will continue to be developed, or that it will retain it's current features and functionality - the developer can turn it into a Minesweeper clone if they feel like it, and there's nothing a business can do but keep using an outdated and thus potentially dangerous version that will eventually become unusable.

You also get a certain level of customer service and corporate communication between the purchasing company and the production company to help resolve issues, which may not exist at all with the alternative.

It's also not always wise to have your business rely heavily on a tool that only sees development through volunteer work by a limited number of disparate people that may come and go, and while I don't know how large the volunteer base is that works on 7zip (it could be just the one guy, it could be a hundred people), to a company it'll never feel as reliable an option as relying on a tool that sees development and maintenance through a paid, full time staff at an established legal entity company with an established reputation.

And speaking for a moment to that established company bit, consider that winrar's company is based in Berlin, within the European Union and under it's rules and laws, which is a far better proposition from a company's standpoint than having to legally deal with an individual guy inside the Russian Federation, especially one that hasn't actually sold your business a product at all.

Anyway, just a few potential thoughts for why tools that do the same job might be preferred by a business, sorry it got a bit long 😅