Your claim that your product will not be discontinued is worthless. If you're so sure of that, put your money where your mouth is, and offer an SLA with a contractual minimum duration you promise to keep the service up, and significant monetary penalties if you fail to meet it. Doesn't sound like a good idea? Then shut up.
But I'm so sick of startups just being R&D for corporations and screwing over their userbase once they get acquired. Or even worse is companies that only get off of the ground because of user support via kickstarter or similar fund raising platforms and then get acquired.
Of course it would be much harder for those companies to raise funds but there's always bootstrapping. It'd be a big win for the consumers of the product and if marketed correctly (something like "Non-Acquirable LLC"), it could become a good way for a startup to show that they put their users first.