All carbohydrates are, at base, sugars. Sooner or later it ends up as glucose and gets burned (or stored as glycogen or as fat).
The important part is how much fiber it's locked up in to slow down absorption and prevent insulin spikes, which are generally things you want to avoid except for right after weight training.
Maltodextrin may as well be sugar. But, if you're only using the product immediately post-weight training workout, it's fine because that's what you want.