I certainly wouldn't say it's trashy, but there are plenty of others who look down on it because they're racist and/or insecure. Plenty of people will say stuff like "You're in America, speak English!" if they hear someone having a conversation in another language. Hell, I grew up a monolingual English speaker and learned a couple other languages as an adult, and I'll get dirty looks sometimes if I'm talking to my coworkers in Spanish, or my sister-in-law in Portuguese. Some people assume that if they show up, whether they're part of the conversation or not, you have an obligation to switch to English as soon as you're in their presence. There are a lot of ignorant people out their who try to mask their racism with a veneer of "proper etiquette" to force others to change language.

If I'm talking with my coworkers about what we're going to eat for lunch, and someone gets pissy about hearing Spanish because they assume we must be talking shit about them, that's not my problem.