Q:

пилигримка - meaning?

While Russian is my first language, I've left Russia more than twenty years ago, and, at moments, I feel that I do not understand the modern usage of some words. For instance, I've only recently discovered the modern meaning of откат. 
The word that puzzled my today is пилигримка: I used to think that пилигримка is female of пилигрим (pilgrim). However, the following usage is rather puzzling:

Она называется даже oфициальнo "всеoбщая пилигримка мoлoдежи всех дoрoг", как-тo так, хoтя пo кoнтингенту oна напoминает русскую радугу.

or

моя любимая пилигримковая еда

Is пилигримка more of an activity (pilgrimage?) or location? How common is this usage?

A:

I think the blog your copied the first excerpt from explains it pretty well:

Пo-пoльски oнo - "pielgrzymka". Этo палoмничествo. вариант целoвания жoпы хэнка, впoлне присущий западнoй катoлическoй культуре, не бoльше.

This is just a calque from the Polish word for pilgrimage (in its Roman Catholic meaning).
In general, polonisms are quite common for terms specific to Roman Catholisicm in Russian: костёл, ксёндз, отпуст, пробощ etc.

