Is it the same snack as roti sai mai?
No. Roti sai mai is an Ayutthaya snack of thin roti wrapped around spun sugar. This guide covers street roti, griddled dough served with a sweet sauce.
Thai Roti · โรตี
If you want a sweet snack on the street, try roti. A thinly stretched dough is cooked on a griddle and served with sweet sauces such as condensed milk or chocolate. There are versions with banana, so it is a good pick when you want fruit and a snack together. If the vendor cuts the roti for you, share it a piece at a time while it is warm.

You enjoy the thin griddled dough and the sweet sauce together. The crispness at the edges and the softness inside change with the ingredients and how it is cooked. In a version with banana, you taste the fruit's sweetness too.
Banana and sauce differ by menu item. Pick the toppings you want first.
In Thailand, roti is also found as a sweet street snack. Roti sai mai from Ayutthaya is a thin roti wrapped around spun sugar, and it is eaten differently from the griddled roti introduced here. If you try both, you get different snacks under the same name of roti.
No. Roti sai mai is an Ayutthaya snack of thin roti wrapped around spun sugar. This guide covers street roti, griddled dough served with a sweet sauce.
Ask about what goes into the dough, the toppings and the sauce, all together. Even a menu item without egg can have an ingredient you avoid in the dough or the condensed milk.
If you want to read more about the food and the regions behind it, these sources are a good place to start. Ingredients and recipes can vary from one restaurant to the next.
Sharing image credit: แอนเดอร์สัน · CC BY-SA 4.0