Sure can! In my experience, MB is the cheapest non-bulk-focused non-specialty grocery store around (phrased as such because I know Aldi also has excellent prices but they have a slightly different customer base), and their selection of "ethnic" or "international" foods is unparalleled. I cook a lot of Asian dishes, and MB is the only Big Chain I can reliably find things like kaffir lime leaves, galangal, lemongrass, fresh turmeric, multiple varieties of kimchi/tofu, etc etc. The same holds true for other cuisines -- the Gloucester MB has a huge Portuguese section, whereas the Chelsea MB has a fantastic Dominican section.

It really hinges on which one and what time you try to shop. The Somerville one is by far the worst in the chain, due to its size and the sheer number of folks that jam themselves into there every day. The NH ones are gigantic and also sell alcohol. It's definitely not for everyone, but it's worth it if you know what you're doing and what you're going for.