And having us pay would probably REINFORCE the monopoly
Plus, actually Google making us pay would probably reinforce the monopoly rather than weaken it, if done right.
They'd probably make us pay for the overall Google experience if they're clever. That means we'd just HAVE to pay, more money to them to forge ahead of competition, but no competition could undercut them, because frankly, once you pay £20 a year to get full access to all the Google property, do you seriously think that it allows the Next Grat Thing from a start-up to emerge and make money out of?
Like, imagine, you're paying that £20 for google mail, maps, earth, search, photo storing, chat, voice, phone, blog, sites, browser and more.
Now, I come with that bright idea that makes mail better. Will you stop paying Google? And because you can't, you probably won't be willing to pay me, so you'll be ok to switch to that new mail service, IF it's free, since you already pay for your mail in a package anyway.
(yes, of course, that would lead to lots of antitrust issues, but that'd still be the rational thing to do for Google. Let's go on crushing the competition, we've got 10 yeas before the competition authorities catch up and the problem will have changed by then anyway)