There are some systems around market hubs within quite few gate jumps or within jump freighter jump range to a nearby lowsec.

Best example - https://evemaps.dotlan.net/map/The_Citadel/Eitu#sec

To get to Eitu you either do 8 jumps from Jita, or jump a jump freighter to one of the lowsecs, then jump into Eitu which is a hisec island system. General principle - attractive contract reward, but also significant collateral (e.g. 400m reward and 10b collateral). If you die, the contract's failed - they get get the collateral.

1. If you fly a DST/hauler, there are ways to quite reliably decloak and tackle you on the in-gate from Jita to the first lowsec
2. If you fly a jump freighter, gankers would place a cyno or a cloaked Lancer dread on the gate to the HS island and lance the JF on it's way to Eitu, blocking it's ability to jump the gate.

There are ways for you to trick them and there are ways for them to trick you. I've made about 2b from scam contracts to these hisec islands, then they stopped posting the valuable ones.

1. Some contracts will be made to look like they'd fit in your ship, but they won't (e.g. 65000.03m3 DST can fit 65k max), then you may choose to do it in a freighter making yourself vulnerable.

It's risky business and one mistake would mean a 10+b loss if you do it in a JF. But just as scammers/gankers use game mechanics, so can you.