Really no way to match Sonic pricing?

Sonic Fiber is now available in my neighborhood. They're offing faster than 1200 Mbps speeds (up and down), no contract, for $39.99 per month. Add $10 a month for modem, and that's still just $50 a month. The only remotely similar deal from Xfinity in my area is $80 a month for 1200 Mbps (down, not up) and that includes a modem, a 1.2TB monthly data cap (which I frequently exceed and then need to pay extra), and a two-year commitment. So, nearly double the price for a significantly weaker package. 

That said, I've been with Xfinity for years and I'd rather not switch if I don't have to. All I need is for Xfinity to work with me a little bit on the price and package they're offering me. Is that really not possible? I tried calling customer service earlier and it seemed that all they could do is put me into another one of these standard $80-per-month packages for two years, and that's a non-starter for me.