Cheap tomatoes

Red equals flavor and nutrients. Red core means ripened on vine, red outside and white core means picked way too early and ripened with ethylene gas right before getting to the store. Brown seeds are bad because they're like brown leaves, they only look that way because they have no nutrients and flavonoids encasing them. Internal preservatives aren't added to fresh fruit because the fruit would have to be fully sanitized (i.e. cooked) to make such a step work. The more you know :)

Are there people waiting for me to comment so that they can downvote or something?

Yes

I knew it

Yeah, what if they just bought a bad tomato? Small samples are bad science.