Tri-tip used to be an unknown, hence under utilized cut of beef. It was mostly used as stew/hamburger. Local areas in Calif knew it's potential and would grill it whole. 35 yr ago it was $0.39/ lb. My uncle owned a small grocery store near Yosemite; shortly after I bought my farm he called and was going to be near my area so he'd stop by. Typical Italian family talk: so how is it, what do you do for fun, what do you eat? I told him I grilled lots of TT, "really!?" He said he grinds it and lots of times his meat man would give it to him free on big orders. He brought a bout 8 when he showed up. We grilled up one and he was jacked. I said they made great sammies too. So from then on I never got another freebie, and he included TT sammies in the deli part of his store
Edit: forgot to say it's now typically $6.99/lb, around July 4th it goes down