To get $75/person you would need to eat (1) TS per day, and also a QS to stand a chance. Unless you eat at a TS that has really expensive entrees/deserts & you get alcohol.
Typically my DW & I will have an inexpensive breakfast, usually just a side of eggs, and a QS during the day. We tend to bring some food for dinner/lunch to fill in so that we aren't eating at the parks or resort for every meal. We do eat at least (2) TS during our trip. For us a dining plan doesn't make sense financially.
The "free" dining plans still make you pay for them in the package pricing. You have to compare what the ticket/room package pricing is with and without the offer. Generally there is a higher price for the "free" DP package so in essence you are paying for it. Just not as much if you did the plan on top of the package. Especially since you have to stay at certain resorts on certain dates.