Man, I really think you should either saddle up, don't block ads, or use a free, non-ad-supported alternative.
Sync is made by a single dev who uses it as his main source of income. It's not made by a corporation. Taking the fruits of someone's labor, that they have priced to make it worth their time, feels kinda shitty to me.
If you really feel it's so much better than the alternatives that you won't even use them, then pay what the person making it feels they need to keep making it.
Same. I write FOSS software in my free time and also paid.