I don't know who is doing the payment processing, specifically, but they're charging a $3 and some change surcharge to the licensing fee to process your payment!
From my credit card online statement when I submitted my app and paid:
12/18/13 12/18/13 ISP CONCEALED CARRY IN SPRINGFIELD IL
<REFERENCE {redacted}>
$150.00
12/18/13 12/18/13 IL ISP FORTE*SERVICE F SPRINGFIELD IL
<REFERENCE {redacted}>
$3.53
From my credit card online statement when I submitted my app and paid:
12/18/13 12/18/13 ISP CONCEALED CARRY IN SPRINGFIELD IL
<REFERENCE {redacted}>
$150.00
12/18/13 12/18/13 IL ISP FORTE*SERVICE F SPRINGFIELD IL
<REFERENCE {redacted}>
$3.53