To determine how many different 6-digit lottery tickets can be sold using the digits from 0 to 9, where the order of the digits matters and each digit can be used multiple times, we can analyze the situation as follows:
- Each of the 6 digit positions in the lottery ticket can be filled by any one of the 10 digits (0 through 9).
- Since the digits can be repeated and the order matters, we have 10 choices for each of the 6 positions.
Thus, the total number of different 6-digit tickets can be calculated using the formula for the number of combinations with repetition allowed:
\[ \text{Total tickets} = 10^6 \]
Calculating that,
\[ 10^6 = 1,000,000 \]
Therefore, the total number of different 6-digit lottery tickets that could be sold is \( \boxed{1000000} \).