It all depends upon the details of implementation. If they're spamming the user with "and before you open this window our sponsor would like to bring you this

It all depends upon the details of implementation. If they're spamming the user with "and before you open this window our sponsor would like to bring you this message..." then that would be pretty bad, and I'd stop using Ubuntu as a result. On the other hand, if you can use the lens to do shopping and get reasonable search results from a range of companies configurable by location, etc, then I think that would be a useful feature. If you're just limited to shopping with one company then that would also be bad (anti-competitive).