Do switches have configuration registeer too? if yes then why cant we use configuration register in switches for password recovery.?

Yes Switches have configuration register and by default value is 0xF [ To check: #show version ]

In case of switches password recovery is done with the help of  mode button and on different series of switches different ways are available for password recovery to let me give you an example :

Steps:
1. Take the console of switch using a program either hyper terminal or putty with terminal settings such as
Bits per second: 9600
Data bits: 8
Parity: None
Stop Bits: 1
Flow Control: Off

2. Unplug the power cable.
3. Power the cable and bring it to the switch: prompt
->Hold down the mode button, while you reconnect the power cable to the switch.this will vary from series - to - series.

2900,3500,3550 - Release the mode button when the LED above Port1x goes down.
2940,2950-When the statuc LED goes out (after 5 sec ), release the mode button.
2960,2970-When the system LED blinks Amber and then turns solid green , release the mode button 
3560,3750-When the system LED turns SOLID green (After 15 sec ), release the mode button

Issue the Flash-init command.
Issue the load_helper command.
Issue the dir flash: command.
rename flash:config.text flash:confi.old
boot
say no
rename flash:config.old flash:config.text
copy flash:config.text system:running-config
change enable and all password and 
write