What did they do during this service?
All manufacturers set the standards for maintenance that needs to be done on their bikes, and at what intervals. What BRP recommends for your F3 can be found in your owners manual. If it is like the 2014 RT (both are the 1330 engine) it will be as follows:
BREAK-IN INSPECTION - 5 000 KM (3,000 MI)
Using BRP Utility and Diagnostic Software (B.U.D.S.), check fault codes and install
required updates.
Replace engine oil and oil filter.
Check clutch fluid level (SM6 model only).
Check brake fluid level.
Check reverse mechanism operation.
Check engine coolant level.
Inspect throttle twist grip operation.
Check lighting system (brake light, hazard warning light, turn signal lights, position
lights, license plate light). Clean brake light switch.
Check operation of control switches.
Inspect the drive belt condition and its tension. Adjust if required.
Check tightening torque of the front wheels lug nuts.
Check tightening torque of the rear wheel axle nut.
Check parking brake operation. Adjust as required.
Check wheels wear. Align front wheels if required.
Check tires pressure. Adjust as required.
Check brake pads and discs condition.
Check passenger handholds looseness.
Check footrests looseness.
Check body panels looseness.
Check operation of storage compartment latches, hinges and key barrels.
If a dealer is trying to get you to guilt you into getting maintenance considerably earlier than BRP recommends then, IMHO, they are trying to rip you off. Perhaps you might want to check with another dealer about when the first service should be done, or even better, contact BRP customer service and explain what you are being told by your dealer.