Hello, thank you for your feedback. Yes, we do show ads in the Free version, there is always Feedly Pro with no ads. Ads in the Free version help us fund new projects and the infrastructure.
That's what paid pro accounts are for. Your product is good enough to merit people giving you money, which lets you develop the features that pro user benefit from, and free users get a taste of, to convince them to switch to a pro account.
Ads as your kickstarter in the absence of a pro account user base? Sure, if you have no other capital to work with, go for it. Still ads even after you have a pro account system in place generating cashflow? Now you're just being bad human beings.