I’ve sent emails like that…it is definitely a thinly-disguised template. I also highly doubt that “the final sponsorship slot” is somehow magically available.
That said, it was always nice to get responses so I could explain myself further. Not saying you definitely should reply. Time is precious, after all, and even a “no” would likely start an even more annoying exchange.
I think the sender is making the same mistake I did, however, by mentioning a discount right up front without fully saying how it would benefit you. I called my emails “diet spam,” in that I’d do at least some research on the promoter and would tailor it to the individual.
Also, I agree with @MelissaJane in that it is pretty poorly formatted.
Again, I’m guilty of annoying people, so I do feel for the sender. But I would say to trust your instincts and ignore it.