Is it necessary to use pickit for pic MCU?
Almost all micro controllers need a dedicated tool to write the firmware in to the chip. Atmel, ST, Microchip all have there own tool. You can buy micro controllers with a boot loader that will enable you to write the firmware with a UART. (example: Picaxe and Arduino)

There are 3th party clones available. A quick search on Ebay for pickit 3: They sell for $11 to $20. 

DM164140 - MPLABXpress Evaluation Board is a nice alternative. It has a programmer build in. It's easy to get started.