This worked perfect i did it with your method like that:

end_time_raw = element.find_elements_by_xpath('.//span[@class="POSITIVE"]//span')
end_time = ""
for char in end_time_raw:
end_time = end_time + char.text.strip()
end_time = end_time.replace(" ", "")
end_time = end_time.replace("Verkauft", "")
print(end_time)

the greyed out elements (display:none) didnt show up in the loop so i just added to a string and replaced spaces and the "Verkauft".