Pros
I found it less stressful than working in food service. It's not a bad place to work, but it's not very fulfilling. If your work and character stand out you may be eligible for promotion and opportunities for growth. I met some nice customers who cared about my well-being and always encouraged me to do better with my life. The people I worked with were down-to-earth, well-meaning, and hardworking.
Cons
The biggest con working at Dollar Tree was the occasional situations where our well-being was at risk due to people coming in to steal. A few times the situation got physical, and/or police were called. You may also experience conflict in the workplace between managers or co-workers. Some people are miserable and don't like their work, and are hard to work with or around. Thankfully I only experienced that with one person on the management level. The pay is low and the salary is not ideal for the long haul. 10 minutes breaks for 6 hours of work is not good.