Participation in a loyalty program and access to an interest-free period tend to increase credit card use at the expense of alternative payment methods, according to this paper.
Using transaction-level data, the authors find that a loyalty program increases the probability of credit card use by 23 percentage points and access to the interest-free period increases the probability by 16 percentage points. Interestingly, the pattern of substitution from cash and debit cards is different in each of these cases. A loyalty program reduces the probability of cash use by 14 percentage points and has little effect on debit card use, while access to the interest-free period has little effect on cash use but reduces the probability of debit card use by 19 percentage points. The authors find these effects to be economically significant and large enough that they can help to explain observed aggregate payments patterns. An implication is that the Reserve Bank reforms of the Australian payments system are likely to have influenced observed payment patterns.