A better analogy would be taking from an unmanned fruit stand that relies on the honor system. Taking something that was not provided for free, and not paying in return, is theft. It's "sent" with the understanding that you're not using an adblocker and thus are viewing the bundled ads.

Regarding things like breadsticks or chips: you have to pay for either them or the meal itself, they have never been "free". There's not really a thing such as "unlimited", because there are always practical limits. Walking out without paying is also theft.