Designers show NIC items so the trades can plan around them. The owner buys them separately, or a later project adds them.
Example: a floor plan shows a scoreboard marked NIC. The gym equipment bidder leaves it out and lists it as an exclusion. The electrician may still need to provide power for it.
Do not price NIC items, and say in your proposal that you left them out. Check for related work that is in the contract, such as backing, power or structure for the NIC item. Watch the addenda, because an addendum can change an item to or from NIC.