She did shop at Ross during the Destiny era. I don't think that she and Becky live near one, so she obviously doesn't go to it anymore.
Yes, she does eat steak "well done" and only that way. IIRC, she never claimed to enjoy or hate red meat and that's remained pretty consistent over the years. She's more into poultry. Even so, she can't cook. She only eats the rest of the spectrum on outings. But remember, she can't fit anywhere. She's massive. It's not like she can easily go to a restaurant (the car ride alone is uncomfortable) and expect to fit there. Not only that, she's extremely self-conscious and doesn't like people staring at her like the anomaly she is. She'd rather hide away inside than deal with the reality she's imposed onto herself by eating anything and everything she wanted to and moving so little.