Dezero Isn’t that just to check if you’re carrying a stolen phone, because phone theft is a huge problem in some countries? Not to spy on people? Do they check your ID as well and correlate that with the IMEI, even when it’s not stolen? Your IMEI is sent to cell towers anyway, if airplane mode is off.
IMEI spoofing is not going to happen. If you want to avoid being spied on based on IMEI, turn on airplane mode even if you don’t have a SIM. Use only WiFi.