Stealing a debit or credit card is usually considered a felony in most states.
However some states theft of a debit card is considered only a misdemeanor unless you steal the debit card and actually use the stolen debit card for purchases or for draining the bank account.
But in most states just the theft of the debit card can be a felony and get the person in prison for 15 to 25 years or even longer.
In some states that make the theft and use of the debit card a misdemeanor you would likely get 1 year in jail and possibly a $1,000.00 fine.
But if you use the card and use more than $500.00 on the stolen debit card then it can go up to a felony that gets you a long time in prison.
Simple theft of the debit card is seen less of a crime than assault in some states because it's just property.